First off, a little about Mint 12 Gnome / Cinnamon...Mint 12 comes with Gnome3 or Gnome Classic / MATE. Gnome Classic is still Gnome3, so keep that in mind.

THIS LOOKS BACKWARDS, BUT THIS IS WHAT"S UP:Gnome2 (IS NOT in Mint12!) uses gconftool-2 and gconf-editor (and your command would be .../desktop/gnome/...)Gnome3 (AKA just Gnome) uses gconftool and gconf-editor (and your command would be .../desktop/gnome/...)MATE uses mateconftool-2 and mateconf-editor (and your command would be .../desktop/mate/...)

In the three above examples, notice how Gnome2 and Gnome3 BOTH share schema settings in the same directory ( /desktop/gnome/... ), and also notice how they both use gconf-editor . This is because their schemas are one and the same, hence why you could NEVER have Gnome 2 and Gnome 3 installed simultaneously. This is coincidentally also why there is a complete fork of Gnome2; MATE. This is so that you can have your Gnome3 base DM -and- have a Gnome2'ish DM installed side by side (generic'd/forked by MATE).

MATE is not a shell over Gnome2, it is it's own FORK of gnome2. This means, MATE has it's own independent way of handling quite a lot of the various Gnome2 functions, and a vast majority of your Gnome2 settings do not have any affect over your MATE settings.

To toggle the keypad on and off, try ONE OF THESE lines:(Depending completely on which Desktop Manager you use)(Set this as a keyboard shortcut)

MATE (which is a FORK of Gnome2):needs :mateconftool-2mateconf-editor (optional GUI)